Bonjour

A = 3/4 + 7/4 x 2/3

A = 3/4 + 14/12

A = (3 x 3) / (4 x 3) + 14/12

A = 9/12 + 14/12

A = 23/12

B = (3/2 - 5/3) : 5/4

B = [(5 x 3) / (2 x 3) - (5 x 2) / (3 x 2)] : 5/4

B = (15/6 - 10/6) : 5/4

B = 5/6 : 5/4

B = 5/6 x 4/5

B = 20/30

B = (10 x 2) / (10 x 3)

B = 2/3.